Experts have warned that pressure is being applied to property buyers.

Estate agents are pressuring house buyers into using their in-house mortgage advisers rather than allowing them to seek independent advice, according to a senior mortgage expert.

Ray Boulger, senior technical manager at John Charcol, said: "The most common tactic seems to be that, when making an offer, buyers are told they must see the in-house mortgage adviser to make sure they can afford the mortgage.

"Otherwise the agent will say they can't recommend acceptance of the buyer's offer, even if the finance has already been arranged in principle."

He added: "In the event that the buyer refuses and decides to use an alternative source, they are invariably informed that the property will remain on the market until, at the very least, the mortgage valuation has been carried out, causing stress to the buyer that they may lose the property and suffer abortive costs."

Some estate agents were even telling clients they wouldn't be allowed to see any of the properties on their books unless the buyer used the agent's mortgage adviser, he said.

Some agents were inserting a clause into the vendor's selling contract which stipulated that they agreed that all potential buyers of their property had to be evaluated by the agent's in-house mortgage adviser.

There are no formal regulations in this part of the housing transaction, and for almost all of us, our mortgage is the largest financial transaction we'll be involved in said Mr. Boulger. "And yet in the whole of the buying process there’s no one acting on our behalf to make sure we’re getting the best deal for our circumstances."

With the estate agents being paid to act on the vendor's behalf, it begs the question: "Who is looking after your financial well-being and making sure that your interests are being looked after?" he added.